Relationship of Anticoagulant Therapy With Cognitive Impairment Among Patients With Atrial Fibrillation: A Meta-Analysis and Systematic Review.

BACKGROUND: At present, it is considered that atrial fibrillation (AF) is a risk factor for cognitive impairment and dementia. It is independent of stroke, but the relationship between anticoagulant drugs and cognitive function in patients with AF is unknown.

OBJECTIVE: The purpose of this study was to complete a meta-analysis of studies and investigate the association between anticoagulant therapy and cognitive impairment in patients with AF.

METHODS AND RESULTS: Two investigators systematically searched the Cochrane Library, PubMed, EMBASE databases, and Web of Science for all studies that present associations. Hazard ratios (HRs) were extracted and pooled. Finally, the 8 studies included 471,057 participants; time in therapeutic range (TTR) <25% versus TTR >75%; (HR 3.02, 95% CI 1.12-8.91; P = 0.03); TTR 25%-50% versus TTR >75% (HR 2.44, 95% CI 0.95-6.22; P = 0.06); TTR 50%-75% versus TTR >75% (HR 1.75, 95% CI 0.90-3.99; P = 0.1); oral anticoagulants (OAC) versus No OAC (HR 0.71, 95% CI 69-0.74; P < 0.00001); and new oral anticoagulants versus warfarin (HR 0.51, 95% CI 0.37-0.71; P < 0.00001).

CONCLUSIONS: OACs significantly reduce the occurrence of cognitive impairment in patients with AF. Compared with warfarin, new oral anticoagulants have an efficiently protective effect on cognition. In the range of INR 2-3, with the increase of TTR, the incidence of cognitive impairment is lower.